A Closer Look at ‘Rogue Planets’ Adrift in the Universe

Not all stars are good parents to their budding planets — some get downright nasty and kick their children into interstellar space.

We’ve found a handful of these free orphaned planets before, and they’re called “rogue planets.” But a study today in Nature Astronomy suggests that the type we’ve seen so far, which are all gas giant sized, are the exception, not the norm.

“Basically, it is much easier to eject an Earth-mass planet than a Jupiter-mass planet,” Przemek Mróz, lead author of